Field of the Invention
The method relates to an identification method for fingerprint, especially to a rapid identification method for fingerprint.
Description of Prior Art
Biometric identification technologies have rapid development due to the strong demand from electronic security applications and remote payment. The biometric identification technologies can be classified into fingerprint identification, iris identification and DNA identification and so on. For the considerations of efficiency, safety and non-invasiveness, the fingerprint identification becomes main stream technology. The fingerprint identification device can scan fingerprint image by optical scanning, thermal imaging or capacitive imaging. For cost, power-saving, reliability and security concerns, the capacitive fingerprint sensor becomes popular for biometric identification technology applied to portable electronic devices.
The conventional capacitive fingerprint sensors can be classified into swipe type and area type (pressing type), and the area type has better identification correctness, efficiency and convenience. However, the area type capacitive fingerprint sensor generally integrates the sensing electrodes and the sensing circuit into one integrated circuit (IC) because the sensed signals are minute and the background noise is huge in comparison with the minute sensed signals. In conventional mobile device, the fingerprint sensor thereof has effective sensing area smaller than 0.5 square centimeters. The number of the extracted minutiae is limited. Therefore, this kind of mobile device is risky when it is applied to mobile payment application. The conventional ID card and credit card suffer to the problems of forging and fraud, and they need to be equipped with fingerprint sensing technology to enhance security. The security of ID card and credit card is more satisfactory when the number of the extracted minutiae is large enough. However, a large-area fingerprint sensor needs more processing time for identification. It is an important issue for this industry to develop a rapid identification method for a large-area biometric sensor.